Aims: Some severe hemodynamic changes are known as problems due to 5% lidocaine spinal anesthesia at the elderly. Such changes, also, may lead to the cardio-vascular or renal problems. The aim of this study was to compare between the hemodynamic changes in two spinal-cord anesthesia methods with 5% lidocaine (the current method) and with low 5% lidocaine dose with 50μg fentanyl in the elderly patients with a systemic blood-pressure increase history in the transurethral resection of the prostate (TURP). 

Materials & Methods: In the two-blinded clinical trial, 148 patients aged more than 50 years with benign prostate hypertrophy, who had referred to 15^th of Khordad Hospital of Gonabad for TURP between 2011 and 2012, were studied. The subjects, selected via simple random sampling method, were randomly divided into two groups (n=74 per group). The first and the second groups underwent spinal-cord anesthesia with the administrations of 5% lidocaine (2cc; 100mg) and 5% lidocaine (1cc; 50mg) + fentanyl (1cc; 50μg), respectively. Blood-pressure and heart-rate were recorded immediately after the anesthesia and at every 5 minutes. Data was analyzed by SPSS 21 software using independent T and Fisher’s exact tests. 

Findings: Mean reductions in the systolic and the diastolic blood-pressures (p<0.001) and mean reduction in the heart-rate (p=0.009) in lidocaine+fentanyl group were significantly lower than lidocaine group. In lidocaine group, ephedrine and atropine administrations were required in 26 and 19 patients, respectively. Nevertheless, no administration either of ephedrine or of atropine was required in lidocaine + fentanyl group (p<0.001). 

Conclusion: Without any hemodynamic instability, low lidocaine dose (50mg) with fentanyl (50μg) may result in sufficient anesthesia and no-pain in the elderly patients with a history of controlled high-pressure, who undergo TURP.